This invention relates to improved jacking apparatus for use in leveling a marine well drilling platform or the like.
Marine platforms are normally supported on `jacket` structures which form a framework projecting downwardly beneath the platform and resting on the bed of the ocean or other body of water in which the platform is located. The jacket has tubular portions forming legs or guides through which piles are driven downwardly into the soil formation beneath the body of water, to anchor the jacket and platform in fixed position.
After the piles have been driven through the tubular members of the jacket and into the earth formation, the platform may be adjusted to a precisely level or horizontal condition by raising one side of the platform relative to the associated piles, and then applying grout between the piles and tubular members to retain the platform in its level condition. A jacking mechanism has heretofore been devised for performing this leveling operation, consisting of a gripping unit which is receivable about and adapted to grip the pile and which is connected by power cylinders to lugs or pad eyes projecting outwardly from the tubular member, in a relation enabling the power cylinders to pull the tubular member upwardly relative to the gripping unit and the pile engaged thereby and to a desired platform leveling condition. The power cylinders in that apparatus are carried by a sleeve received about the pile above the upper end of the tubular member.